Voice over DSL: good for slashing your phone bill?

The kit is just hitting Europe

Voice over IP connections has been a much talked about (but infrequently used) networking technology for a number of years but kit to allow voice and data over DSL links has just being introduced to Europe.

VoDSL (voice over DSL) technology, which was displayed by a number of firms at the CeBIT show in Hangover, Germany, is being targeted at small businesses who are likely to be interested in the savings in call charges the technology can bring. By contrast VoIP has been heavily promoted by firms like Cisco as a means for larger firms to integrate their voice and data networks.

Eric Warren, of VoDSL equipment manufacturer Jetstream, said that the technology allows telecoms resellers and alternative carriers to offer bundled services including voice, fax and data that cost customers up to 20 per cent less than paying for them individually.

For alternative carriers, the technology offers a way to improve customer loyalty by tying them into value-added services and encourages individual users to spend more.

Jetstream's access devices use quality of service features in the transport protocol used by almost all DSL connections (which is called ATM or Asynchronous Transfer Mode), which means users would get a good quality voice connection.

Because Jetstream kit uses protocols native to DSL instead of first wrapping IP packet in ATM cells, services are delivered with a lower overhead, according to the firm.

Only the symmetrical part of an DSL connection can be used for voice traffic which means, in practice, only two to four voice lines can be delivered per ADSL link. More voice ports are available on higher-speed links.

Warren said Jetstream is talking to around 15 alternative carriers throughout Europe about the technology, some of whom are in advanced stages of testing its xDSL modems, which feature voice capabilities. ®